Original Articles
Copyright ©2009 The WJG Press and Baishideng. All rights reserved.
World J Gastroenterol. Sep 7, 2009; 15(33): 4150-4155
Published online Sep 7, 2009. doi: 10.3748/wjg.15.4150
Measuring Ca2+ influxes of TRPC1-dependent Ca2+ channels in HL-7702 cells with Non-invasive Micro-test Technique
Zhen-Ya Zhang, Wen-Jun Wang, Li-Jie Pan, Yue Xu, Zong-Ming Zhang
Zhen-Ya Zhang, Li-Jie Pan, Zong-Ming Zhang, Department of General Surgery, Digestive Medical Center, The First Affiliated Hospital, School of Medicine, Tsinghua University, Beijing 100016, China
Wen-Jun Wang, Yue Xu, Xuyue (Beijing) Science and Technology Co., Ltd., Haidian District, Beijing 100080, China
Author contributions: Zhang ZM and Zhang ZY designed the research and wrote the paper; Zhang ZY, Wang WJ and Pan LJ performed the main research; Zhang ZM and Xu Y provided vital reagents and analytical tools.
Correspondence to: Zong-Ming Zhang, Professor, MD, PhD, Department of General Surgery, Digestive Medical Center, the First Affiliated Hospital, Medical School, Tsinghua University, Beijing 100016, China. zhangzongming@mail.tsinghua.edu.cn
Telephone: +86-10-64372362 Fax: +86-10-64361322
Received: May 8, 2009
Revised: July 21, 2009
Accepted: July 28, 2009
Published online: September 7, 2009

AIM: To explore the possibility of using the Non-invasive Micro-test Technique (NMT) to investigate the role of Transient Receptor Potential Canonical 1 (TRPC1) in regulating Ca2+ influxes in HL-7702 cells, a normal human liver cell line.

METHODS: Net Ca2+ fluxes were measured with NMT, a technology that can obtain dynamic information of specific/selective ionic/molecular activities on material surfaces, non-invasively. The expression levels of TRPC1 were increased by liposomal transfection, whose effectiveness was evaluated by Western-blotting and single cell reverse transcription-polymerase chain reaction.

RESULTS: Ca2+ influxes could be elicited by adding 1 mmol/L CaCl2 to the test solution of HL-7702 cells. They were enhanced by addition of 20 μmol/L noradrenalin and inhibited by 100 μmol/L LaCl3 (a non-selective Ca2+ channel blocker); 5 μmol/L nifedipine did not induce any change. Overexpression of TRPC1 caused increased Ca2+ influx. Five micromoles per liter nifedipine did not inhibit this elevation, whereas 100 μmol/L LaCl3 did.

CONCLUSION: In HL-7702 cells, there is a type of TRPC1-dependent Ca2+ channel, which could be detected via NMT and inhibited by La3+.

Keywords: Non-invasive Micro-test Technique, Ca2+ channels, Transient Receptor Potential Canonical 1, Gene expression, HL-7702 cells